DE2429029A1 - COATED SYNTHESIS PAPER SUITABLE FOR OFFSET PRINTING - Google Patents

Description

DR.-ING. WALTER ABITZ ^ _{ΟρΛβη # l8 June}

DR. DIETER F. MORF 'Postal Address

DR. HANS-A. BROWN

8 Munich 86, P.O. Box 860109

Patent attorneys "Pienzenauerstraße 28

O / O Q Π 0 Q Telephone 483225 and 486415

L · * Λ L · v3 U ζ, ν Telegrams: Chemindus Munich

Kanzaki-23

Kanzaki Paper Manufacturing Co., Ltd., Tokyo, Japan Toray Industries, Ine.,! Tokyo, Japan

Coated synthetic paper suitable for offset printing

The present invention relates to an improved synthetic coated paper and a method for its manufacture. In particular The invention relates to an improved coated synthetic paper produced from a polyolefin synthetic paper material, which has a coating layer suitable for offset printing on its surface.

Polyolefin synthetic paper possesses compared to natural pulp the advantage that, in contrast to the latter, it has a good heat sealability, both higher dry and wet strength and good Dimensional accuracy results. Attempts have already been made to use a pigment-coated Manufacture synthetic paper, in which these advantages of the polyolefin synthetic paper material are exploited. The Japanese Offenlegungsschrift 29. 607/1972 describes, for example, a coated synthetic paper with a coating layer consisting of inorganic Pigments such as clay, calcium carbonate, satin white (CaI-

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ciumsulfoaluminate) or talc, and adhesives such as casein, starch or styrene / butadiene latex, produced on a base or backing paper which is either made entirely of synthetic polyolefin paper or a mixture of synthetic polyolefin paper with natural pulp and / or another synthetic paper material. One such "coated synthetic paper however, it has the disadvantage that the printing ink transfer, especially in multi-color offset printing, does not take place smoothly. In multi-color offset printing, the fountain water generally remains on the sheet surface during the printing process when the The surface of the coated paper has a poor absorption capacity for it. Due to the presence of the washer fluid on the paper surface, the paper is prevented from receiving the printing ink to be transferred onto its surface by a printing cylinder records. Thus, if an aqueous one consisting essentially of a pigment component and an adhesive component Coating agent is applied to the base paper produced from polyolefin synthetic paper and the coated paper is then dried the coating agent penetrates the base paper more slowly than in the case of one made from natural cellulose Raw paper sheets. The adhesive contained in the coating agent migrates therefore, when drying to the surface of the coating layer of the paper sheet, which leads to an accumulation of the adhesive in the coating layer near the surface. This can result in that the coated synthetic paper does not have good absorption capacity for the wiping water. Even if a relatively small one Amount of polyolefin stock used occurs locally inadequate wiper water absorption. Using a relatively high amount of polyolefin paper stock does the bad Wiping water absorption on almost the entire surface of the paper.

On the other hand, with a view to handling and saving transport costs, the pigment-coated paper is light in weight advantageous. When the thickness of the base paper is reduced for this purpose, strength, whiteness and opacity are deteriorated of the paper. It was hardly possible to remedy the aforementioned disadvantages with the help of a conventional pigment-coated,

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to eliminate the paper pulp obtained.

The object of the invention is primarily to provide a for to create improved coated synthetic paper suitable for offset printing. Furthermore, it is the object of the invention to provide a improved coated synthetic paper with high opacity, good whiteness and good dimensional accuracy are available place. In addition, an improved coated synthetic paper is to be created according to the invention, which is relatively easy, however, it is sufficiently stiff. The object of the invention is furthermore to provide an improved method for producing the aforementioned to provide coated synthetic paper. The following detailed description leaves the object and advantages recognize the invention.

The object of the invention can be achieved in that a coating layer is applied to a polyolefin synthetic paper, which is formed from a pigment component and an adhesive component, part of the pigment component being an organic polymer pigment in the form of fine-grained particles. More specifically, the most suitable for offset printing, coated synthetic paper of the invention includes a base paper sheet from Pasermaterial, formed by the at least 5 wt. -Fo of polyolefin pulp, and a coating applied to at least one surface of the base paper sheet coating layer consisting essentially of an adhesive component and a pigment component is built up, wherein at least part of the pigment component is an organic polymer pigment in the form of fine-grained particles.

It has been found that the offset printability of the polyolefin paper Fabric produced synthetic paper is thereby unexpectedly and significantly improved that one on the synthetic paper Coating layer produced with the aid of a coating composition containing fine-grained particles of organic polymers. The present invention is thus characterized by a combination of a polyblefin synthetic paper with a special organic one Coating composition containing polymer particles (hereinafter always referred to as "coating agent").

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Preferably 5 to 95 wt .- # of the fiber material of the carbon paper sheet formed from polyolefin paper stock. The remaining part of the fiber material can be derived from natural cellulose.

At least 5% (in particular at least 10% by weight ) (dry substance) of the pigment component can represent an organic polymer pigment in the form of fine-grained particles. The pigment component can consist of a mixture of an organic polymer pigment in the form of fine-grained particles and an inorganic pigment.

The proportion of the adhesive component in the coating layer can be 5 to 100 parts by weight, particularly 8 to 35 parts by weight, each based on 100 parts by weight (dry substance) of the Coating layer contained pigment component.

The organic polymer pigment used in the invention preferably consists of fine particles composed of an organic polymer having a deformation temperature of more than 30 C, in particular more than 5O ⁰ C, according to ASTM test standard D 648. The organic polymer pigment preferably consists of fine-grained particles with an average grain size of 0, 1 to Λ jix »

"In a preferred embodiment of the invention, there is the organic polymer pigment from fine-grained particles of polystyrene, polymethyl methacrylate or their copolymers with any other vinyl monomer.

The application amount of the aforementioned organic polymer pigment

The coating agent containing should be at least 0.5 g / m 2, preferably 3 to 30 g / m (dry matter).

The polyolefin paper used according to the invention he material can consist of fibrils, the specific surface area at least 0.7 g / m. The polyolefin stock can be made from an olefin polymer and a hydrophilic polymer.

The invention will now be explained in more detail,

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Das Fasermaterial.des raw paper of the coated paper according to the invention Synthetic paper consists of a polyolefin paper stock containing a hydrophilic component. Examples of polyolefins that are suitable for the polyolefin paper stock are horopolymers, produced by the polymerization of olefin monomers such as ethylene, propylene, 4-methylpentene-1, butene-1 or styrene can be obtained and copolymers of these olefins. Included are copolymers, which through. Polymerization of these olefins with copolymerizable Vinyl monomers are obtained, such as ethylene / vinyl acetate -Copolymer and ethylene / acrylic acid salt copolymer.

Examples of the hydrophilic component are polymers with a hydroxyl group such as polyvinyl alcohol, saponified ethylene / vinyl acetate copolymer, Polyvinyl alcohol with a radical grafted vinyl monomer, such as styrene or methyl methacrylate, also Polymers and copolymers obtained by polymerizing monomers with carboxyl groups, e.g. acrylic acid, methacrylic acid, Butentricarboxylic acid, maleic anhydride, itaconic acid and its partial esters, polymers with an amide group, such as polyacrylamide, as well as other hydrophilic polymers such as polyethylene oxide and carboxymethyl cellulose. These hydrophilic components can be incorporated into the polyolefins by polymer blending and / or graft copolymerization will. The weight ratio of the hydrophilic component to the polyolefin in the fiber material is preferably in the range of 0: 100 to 40:60, especially from 1:99 to 30:70. One can the polyolefin composition for making the polyolefin paper stock incorporate any conventional heat stabilizers, antioxidants, and UV absorbers. Inorganic powder materials, such as silica, alumina, talc, calcium carbonate, calcium sulfite and calcium sulfate, can also be used as fillers be added. The polyolefin fiber material is for example through emulsion ~ relaxation spinning, relaxation spinning, the dissolution method, monaxial stretching and cleavage or melt spinning is produced. Of these processes, the emulsion - Relaxation spinning, relaxation spinning and the solution shear method preferred, especially emulsion relaxation spinning.

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The emulsion relaxation spinning process as such is, for example in U.S. Patent 3,808,091. At the Emulsion relaxation spinning produces the fiber material for the paper stock by using a polyolefin, a solvent for the polyolefin and a non-solvent mixed, one from the mixture obtained by heating with vigorous stirring produces hot emulsion in which the polyolefin is dissolved, and the heated emulsion under high pressure through a nozzle opening squeezes out. For example, polyethylene is used as the polyolefin, hexane as the solvent, and sodium laurylbenzenesulfonate as the surface-active one Agent and water containing polyvinyl alcohol as a dispersion medium or non-solvent. The one by crushing of the spun fiber material obtained has synthetic paper has a high specific surface area and includes a hydrophilic polymer and a surface active agent. The one on this Synthetic paper obtained in this way is readily suspendable in water and has a good self-binding capacity.

In the relaxation spinning process, an organic solvent is used dissolved polyolefin pressed out through a nozzle opening at high temperature and high pressure. With this procedure that can Spun fiber material hardly contain any hydrophilic polymer and must therefore during or after the comminution with a treated hydrophilic polymers and a surface active agent to give it hydrophilic properties. Relaxation spinning as such is for example in the U.S. Patent 3,081,519.

The solution shear method is as such in the German patent 2,058,386 and British patent specification 868,651. For example, a polymer solution is introduced into a non-solvent for the polymer in order to precipitate the polymer, and subjects the deposited polymer to a shear force, whereby a fiber material is obtained. One can use P as eimaterial also produce by applying a shear force to the polymer, which, in the stage of polymerization of an olefin separates. That obtained in this way by the solution shear method

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Fiber material becomes hydrophilic in a subsequent process step made, as is the case with relaxation spinning.

Some hydrophilic components, such as polyvinyl alcohol, saponified ethylene / yinylacetate copolymer, polyethylene oxide, polyacrylamide and modified starch may be any of the foregoing Methods obtained fiber material after the comminution or. Fiber treatment can be added to make the latter easier is made dispersible in water and so that it is given a good self-binding capacity.

The synthetic polyolefin paper generally has a complex microfibril or micromembrane pain structure.

The specific surface of the synthetic paper material is primarily

2 2

preferably more than 0.7 m / g, in particular more than 1 m / g (measured according to the BET method).

When the specific surface area of synthetic paper is less

than 0.7 m / g, the aforementioned can be used according to the invention

Not achieving goal.

The polyolef in synthesis paper produced in the above-mentioned manner can be processed into paper sheets or webs on a conventional paper machine alone or with a cellulose pulp. At least 5 weight fo the 3? Asermaterials of the paper sheet to be formed from the polyolefin synthesis paper stock. If the paper sheet has a proportion of the polyolefin synthetic paper stock of less than 5% by weight, the aforementioned various advantages attributable to the polyolefin paper stock cannot be achieved.

The paper sheet is in particular made from a mixture of polyolefin paper stock made with natural cellulose, although it can also be made from a blend of a polyolefin paper stock with any other synthetic paper stuff can produce. When producing the paper sheet axis a mixture of polyolefin paper

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staff with natural pulp is the weight ratio of this Ingredients preferably 5:95 to 95: 5.

Conventional Fillers, sizing agents and dyes are added without the advantages according to the invention being impaired.

A coating agent which can be used according to the invention is an aqueous one Composition consisting essentially of a pigment component and an adhesive component. At least part of it the pigment component contains fine particles of an organic polymer.

The fine-grained particles of an organic polymer are preferably spherical and / or spheroidal in shape, although they may have any other shape. The particles have an average grain size of 0.1 to 1 μm. It is necessary that these particles do not form a film under the conditions of the application and drying of the coating agent and the finishing of the coated paper. The organic polymer particles preferably have a distortion temperature of at least 3O ⁰ C (defined and measured in accordance with ASTM test standard D • 648), in particular of at least 50 C.

The aforementioned particles can be obtained by emulsion polymerization of a suitable monomer or a mixture of such monomers or by emulsifying a suitable polymer, which by another method, such as by Bulk or solution polymerization was generated. The fine-grained particles can then be used according to any desired conventional fine grinding method.

Examples of suitable organic substances for the fine-grained Particles are polymonovinylidene aromatics, such as polystyrene, poly (ot-methylstyrene), poly (4-ethylstyrene) or poly (1-vinylnaphthalene), Polyolefins and polyhalogenolefins, such as polyvinyl chloride,

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, Poly (hexafluoropropylene), polyethylene, polypropylene, poly (1-bu-X.ten), Poly (4-methyl-1-pentene), polyvinylidene chloride, poly (1,2- -difluoroethylene), esters of ß-ethylenically unsaturated acids, such as polymethacrylate, polychloroacrylate and polychloromethacrylate, e.g. poly (methyl methacrylate), poly-cisopropyl chloroacrylate), poly- - (2-chloroethyl methacrylate), poly (cyelohexyl chloroacrylate), poly- - (methyl chloroacrylate), polyvinyl acetate, polyallylacetate or polyvinyl propionate, as well as other polymers, such as poly (ethylene 1,5-naphthalate), polyethylene terephthalate, poly (hexamethylene adipamide), Poly- (6-capramide), poly-cdekamethylene adipamide), polycarbonate, Polyacetal, polyvinyl formal or polyvinyl butyral. Copolymers of Basic monomers of the aforementioned polymers, e.g. ethylene / vinyl acetate copolymer or ethylene / propylene copolymer are also suitable.

Various other copolymerizable monomers such as conjugated diethylenically unsaturated monomers, alkyl acrylates and acrylonitrile, may be present in a small amount as comonomers in the aforementioned suitable polymers. Typical examples of such conjugated diethylenically unsaturated monomers are 1,3-butadiene, Isoprene, 2-chloro-1,3-butadiene, and divinylbenzene. Typical examples for such alkyl acrylates are methyl acrylate, ethyl acrylate, n-propyl acrylate, sec-butyl acrylate and n-butyl acrylate. tf, ß-Ethylenic unsaturated carboxylic acids and their anhydrides, such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid and maleic anhydride, can also serve as copolymerized components of the suitable polymers. Copolymers such as ethylene / Acrylic acid copolymers, ethylene / maleic anhydride copolymers or styrene / maleic anhydride copolymers, for example, also form polymers which can be used according to the invention.

Of the aforementioned organic polymers, vinyl polymers and vinyl copolymers are preferred in the present invention.

The coating agent which can be used according to the invention is an aqueous one coating agent, which by. Dispersing the foregoing organic polymer particles alone or with suitable inorganic

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ganisehen pigments in an aqueous containing an adhesive Solvent or by mixing an organic polymer emulsion and an adhesive with an optional Inorganic pigment-containing aqueous solvent prepared -can be. As adhesives for the aforesaid coating agent the natural and synthetic conventionally used for the production of known aqueous pigment coating agents are suitable Glue. Examples of this are protein materials, such as casein, soy protein and gelatin, starch or their derivatives, such as dextrin, raw starch, oxidized starch, esterified starch, etherified starch, cationic starch or phosphated starch, Cellulose derivatives, such as carboxymethyl cellulose or hydroxyethyl cellulose, Latiees of conjugated diene polymers such as styrene / butadiene copolymers or methyl methacrylate / butadiene copolymer, Acrylic polymer latices, such as polymers or copolymers of acrylic esters and / or methacrylic esters, vinyl polymer latices such as Ethylene / vinyl acetate copolymer, through functional groups such as Carboxyl group modified polymer latices, and synthetic resin adhesives, such as polyvinyl alcohol, olefin / maleic anhydride copolymers or mineral resins. These adhesives can also be used in the form of a mixture »

Examples of inorganic pigments which can be mixed with the fine-grained particles of an organic polymer are Kaolin, clay, calcium carbonate, calcium silicate, calcium sulfate, calcium sulfite, Titanium oxide, aluminum hydroxide, barium sulfate, zinc oxide, Satin white, talc and colloidal silicon dioxide. The preferred mixing ratio of the organic polymer particles with inorganic ones Pigments is in the range from 100: 0 to 5:95 (parts by weight Solid substance) - If the admixed amount of inorganic pigments exceeds the aforementioned range, the advantageous do not achieve effects according to the invention. The mixing ratio is in particular in the range from 100: 0 to 10:90 ' (Parts by weight of solid substance). Because different adhesives have a different one Have adhesive power, their proportion is not determined. The amount of glue is generally in the range of 5 up to 100 parts by weight (preferably 8 to 35 parts by weight),

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added pigments (including the organic polymer particles) per 100 parts. The coating agent obtained in this way can of course contain additives, for example dispersants, insolubilizers, preservatives, flow modifiers, colorants and foam regulators. The aforementioned coating agent is applied to the base paper produced from polyolefin synthetic paper with the help of coating devices arranged on or outside the paper machine with suitable coating devices, for example by means of smooth doctor coating machines (blade coaters), slot nozzle coating machines, roller coating machines, brush coating machines , Curtain coating machines, roller squeegee coating machines (Champflex Coater), bar coating machines, engraving or gravure coating machines, spray coating machines or by coating in the size press. Han should not raise the temperature so much that the organic polymer particles are deformed by the heat and form a hanging film.

The proportion of the coating agent to be applied depends on its composition or on the quality of the paper and is therefore not specified. In order to improve the printability of the offset ' To achieve pressure, however, the effective proportion is at least 0.5 g / m, preferably 3 to 30 g / m (dry weight per side of the Paper). The beneficial effects ascribed to the invention cannot be obtained when the coating agent is used in an amount less than 0.5 g / m 2 is applied. The upper limit of the Application quantity of 30 g / m is based solely on economic factors Points of view. The coating layer can be applied once a coating agent as well as by applying the same or another coating agent twice or more times.

The coated synthetic paper obtained in the manner described can be calendered, gloss calendered and high gloss calendered as well as the end bear used in conventional coating technology methods of training. In performing this Treatment methods should be such high temperatures and / or pressures that the polymer particles deform and

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hanging film cannot be used.

The way the offset printability is made possible by the invention is improved is not cleared up. A related one Theoretical explanation is that when a coating agent containing organic polymer particles is applied to the Surface of the synthetic paper described migrate the organic polymer particles to the surface of the coating layer, whereby a microporous and incoherent coating layer is formed with such a nature that the mopping water at its Application is effectively absorbed.

The coated synthetic paper of the present invention has the large size Advantage that there is not only good printability for offset printing, but also high whiteness, high light transmission, good water resistance and good dimensional stability and that a light coated paper without sacrificing the cheap Properties of polyolefin fiber paper can be produced.

The preferred embodiments of the present invention are discussed below.

The examples are intended to explain the invention in more detail, but without it to restrict. In the examples, parts and percentages mean parts by weight and percentages by weight, unless otherwise is specified.

Example 1 to 5

100 parts of polypropylene (ßjj = 1.3 dl / g) and 1070 parts of methylene dichloride are mixed to form a slurry. This is then mixed with 1200 parts of an aqueous polyvinyl aiko ho 11 solution containing 10 parts of polyvinyl alcohol (degree of polymerization: 1400; saponification number: 99 / S) and 2 parts of dodecylbenzenesulfonate. This mixture is placed in an autoclave and then heated with stirring, an emulsion being formed. When the emulsion has reached a temperature of HO ⁰ C, it is pressed out through a nozzle, whereby a fiber material is obtained. One puts one

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A percent aqueous suspension of the fiber material, which is generally ground with the aid of a Sprout Waldron disc refiner. The specific surface area of the synthetic paper material obtained is 15 m 2 / g. The synthetic paper is mixed with a natural pulp mixture of 20 parts of NBKP (bleached softwood sulfate pulp j CSF 420 cm ³ ) and 80 parts of LBKP (bleached hardwood sulfate pulp ₉ CSP 400 cm ³ ) using different mixing ratios given in Table I. Then 0.5 part of rosin per 100 parts of paper stock and 2.5 parts of aluminum sulfate per 100 parts of paper stock are added. The result is a pulp with a fabric density of $ 0.3. A paper sheet is then produced on a laboratory fourdrinier paper machine and treated with polyvinyl alcohol (degree of polymerization: 1700; saponification number: $ 99) using a size press.

2 This gives a base paper of 40 g / m 2.

Separately, 32.4 parts of kaolin of quality No. 1, 25.2 parts of kaolin of quality No. 2, 14.4 parts of aluminum hydroxide and 28 parts (solid substance) of a polystyrene emulsion (deformation temperature at 18.5 kg / cm ι 94 ⁰ Cj average particle size: 0.5ja) dispersed in water with the aid of a high-speed mixer with sufficient stirring so that a slurry with a solids content of 67 ° is obtained. This slurry is mixed with 7 parts (solid substance) of a solution of oxidized starch (degree of oxidation: 0.013), 16 parts (solid substance) latex of carboxylated styrene / butadiene copolymer (styrene / butadiene: 60:40), a coating agent with a final concentration of $ 58. This coating agent is then applied to the above-mentioned base paper in proportions (dry substance) of 7 g / m (fiIz side) or 9 g / m (sieve side) with the aid of a smoothing doctor coating machine. The coated paper is then dried and high-gloss calendered. The various properties of the coated papers obtained are shown in Table I.

Comparative example 1

100 parts of the same natural pulp mixture as used in the Examples 1 to 5 are used, 0.5 parts of rosin and

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2.5 parts of aluminum sulfate are mixed to a pulp with a density of 0.3%. Then you create in the In the manner described in Example 1, a base paper of 40 g / m 2.

Separately, 45 parts of # 1 quality kaolin becomes 35 parts Kaolin of quality no. 2 and 20 parts of aluminum hydroxide are added using a Sehnell mixer with sufficient stirring in water a slurry with a solids content of 67 ^ dispersed. 7 parts (solid substance) of a solution of oxidized starch (degree of oxidation: 0.013) and 14 parts are added to the slurry (Solid substance) styrene / butadiene latex (the same as in Example 1 to 5) and thereby receives a coating agent with a Final concentration of $ 58. The coating agent is with the help of a Smooth doctor coating machine in proportions (dry matter) of 7 g / m (felt side) or 9 g / m (wire side) on the aforementioned Applied and then dried and high-gloss calendered. A coated paper is obtained, the properties of which are shown in Table I.

Comparative example 2

This example is the same as Comparative Example 1 except that the same base paper as in Example 3 is used. The properties are also shown in Table I.

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Kanzaki-23 1 a b e 1 / 6- 3 4th VJl 2429029 le I 19th example 13th 10 0 Comparative
example 76 2 '52 40 0 1 2 Mixing ratio
nis of the paper
fabric (£) VJl 35 50 100 NBKP. 16 20 13 LBKP 64 80 52 Polyolefin
- paper stock 20th 0 35

Properties of the coated paper "Density (g / cm ³ ) 1.09 Whiteness (fo) 78.9

Opacity - opacity (<fi) 80.4 gloss {<$) 56.0 water resistance

Printability in offset printing

B A

1.05 79.5

83.8 55.8

A A

1.00 83.5

87.1 52.3

A · A

0.93 85.6

90.8 50.4

A A

0.83
89.8

95.3
49.5

A.
B.

1.13 1.05

76.6 82.1

78.8 85.6

40.6 36.5

D.
B.

C D

Remarks:

I) Methods for checking paper quality

1) Whiteness: determined in accordance with JIS P 8123 (the higher the value, the greater the lightness);

2) Opacity: determined in accordance with JIS P 8138 (each the higher the value, the more opaque); ·

3) Gloss: determined with the aid of a 75 ° mirror gloss meter (the higher the value, the greater the gloss);

4) Water resistance: 2 drops of water are dripped onto the coated surface, which one 15 times with rubs the pinger. The water droplets are then transferred to the surface of a black glass plate. After drying, the degree of whiteness is determined

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Plate.

5) Offset printability: testing the offset printability is carried out with the help of an RI printability tester (Akira Industry Co.) with two printing units, One of which is used to apply fountain water, the other to apply a printing ink. Man determines the ink absorption capacity of the paper.

II) Assessment of the water resistance and offset printability A: excellent
B: good
C: bad
D: very bad

The above remarks also apply to Tables 2 to 5.

The coated papers obtained according to Examples 1 to 5 are superior to those of Comparative Example 1 in terms of whiteness, opacity, water resistance and gloss. The coated paper according to the invention also has excellent offset printability.

In contrast, the coated paper obtained according to Comparative Example 2 has very poor offset printability.

In Examples 6 to 8 below, the coated papers are produced in the same manner as in Example 3, except that one uses different synthetic paper materials in each case.

Example 6

A mixture of 95 parts of high density polyethylene (melt index according to ASTM D 1238: 6 g / 10 min) as polyolefin, 5 parts of polyvinyl alcohol (degree of polymerization: 1400; saponification number: 99 as a hydrophilic polymer, 900 parts of hexane as a solvent and 3 parts of sodium dodecylbenzenesulfonate as a surfactant is emulsified under the same conditions as in Example 1.

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The dispersion obtained is used for the production of a fiber material squeezed out through a nozzle. The after / grinding with the help synthetic paper obtained from a Sprout Waldron disc refiner

stoff "has a specific surface area of 15.9 m / g (according to the BET method).

Example 7

A mixture of 75 parts of polypropylene (/ nJ = 2.3 dl / g; melt index = 1.5 g / 10 min), 5 parts of polyacrylamide, 20 parts of ethylene / vinyl acetate copolymer (degree of polymerization: 2000; ethylene / vinyl acetate = 85: 15) and 30 parts of calcium cartionate powder is emulsified under the conditions described in Example 1. The dispersion obtained is pressed through a nozzle to produce a fiber material. The. specific surface of the ground paper stock is 21.5 m / g (according to the BET method).

Example 8

A mixture of 77 parts of high density polyethylene (melt index = 0.3 g / 10 min) and 18 parts of ethylene / sodium acrylate copolymer (Melt index = 5 g / 10 min; ethylene / sodium acrylate = 90:10) as polyolefins, 5 parts of polyethylene oxide (degree of polymerization: · 100,000) as a hydrophilic polymer, 900 parts of hexane as a solvent and 4 parts of sodium laurylbenzenesulfonate is among the in Example 1 described conditions emulsified. The dispersion obtained is used for the production of a fiber material by a Nozzle pressed out. The synthetic polyolefin paper stock has after grinding a specific surface area of 18.9 m / g (according to the BET method). ·

Example 3 to 5

In Comparative Examples 3 to 5, the same base papers are used as in Examples 6 to 8. The other conditions are the same as in Comparative Example 1.

The various properties of the coated produced according to Examples 6 to 8 and Comparative Examples 3 to 5 Papers are shown in Table 2.

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Table II

Example 6 7

Mixing ratio of the paper stock Cs &)

NBEP 13th 13th 13th 13th 13th 13th LBKP 52 52 52 52 52 52 Polyolef in-
- paper stock 35 35 35 35 35 35

Properties of the coated paper

Density (g / cm ³ ) 1.01 Whiteness ($) 84.2 Opacity 85.4 Permeability (S) Gloss {56)

Water resistance

Printability in offset printing

50.3 A

1.03 83.8 88.6

49.7 A

1.00 84.6 87.4

51.2 A

Comparative example 3 4 5

1.07 1.09 1.05 83.0 82.6 83.0 84.0 87.2 85.6

35.1
C.

33.4 C

35.8 C

From Table II it can be seen that those obtained according to Examples 6-8 coated papers the papers produced according to Comparative Examples 3 to 5 with regard to gloss and water resistance and are superior to offset printability. In particular the offset printability of the comparative examples 3 to 5 coated papers produced is remarkably poor «

In Examples 9 and 10 below, different methods are used manufactured polyolefin synthetic paper materials used «

Example

A synthetic polyolefin paper is made by the solution shear method. 5 parts of high-density polyethylene (melt index = 0.3 g / iO min) in 95 parts of xylene at one temperature

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solved above TOO ^{0 C.} This gives a 5 percent XyIo 1 solution, which is gradually poured into cold ethanol (a non-solvent for polyethylene) with the aid of a vigorously agitated juice mixer, using a strong eye. The paper pulp material obtained is treated with the same polyvinyl alcohol as in Example 1 and ground using a Sprout Waldron disc refiner. The specific surface of the paper stock is

6.3 m / g (according to the BET method).

35 parts of the synthetic paper stock obtained in this way will be with a natural pulp mixture of 13 parts NBEP and 52 parts of LBKP mixed in a manner analogous to Example 1 to 5 to produce a base paper.

Then an organic polymer particle-containing one is brought Coating agent on the Eohpapierblatt. The coating agent is the same as in Examples 1 to 5i and the coating method corresponds to that described in Examples 1 to 5.

Example 10

A synthetic polyolefin paper is produced by the solution-relaxation spinning method. (6 g / 10 min melt index =) solution obtained in 1 liter of hexane are pressed one by dissolving 100 g of high density polyethylene with vigorous stirring at 180 G ⁰ through a nozzle. The continuous fiber material obtained is cut to a length of about 5 mm and ground using a Sprout Waldron disc refiner. Polyvinyl alcohol (same as in Example 1) and sodium dodecylbenzenesulfonate are added. The specific surface of the paper stock is 16.7 κ / gC according to the BET method).

A coated synthetic paper is produced in a manner analogous to that in Examples 1 to 5. The other conditions are the same as in example 9

Comparative example 6

A coated synthetic paper is made using the

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the same base paper as in Example 9 and the same coating agent as in Comparative Example 1. The other conditions are the same as in Example 9.

Comparative example 7

A coated synthetic paper is prepared using the same Base paper as in Example 10 and the same coating agent as in Comparative Example 1. The other conditions are the same as in example 10.

The various properties of the coated synthetic papers obtained according to Examples 9 and 10 or Comparative Examples 6 and 7 can be seen from Table III. Table III shows that the coated papers obtained according to Examples 9 and 10 are clearly superior to those of Comparative Examples 6 and 7 with regard to gloss, water resistance and offset printability.

T a b e 1 1 e III

example 10 Comparative example 7th 9 6th Mixing ratio s of the paper stock (f>) 13th 13th NBKP 13th 52 13th 52 LBKP 52 35 52 35 Polyolefin paper stock 35 35

Properties of the coated paper

Application weight (g / m) (felt side / wire side) Paper weight (g / m) Density (g / cm) Whiteness (f ₀ ) Opacity ( fi) Gloss (^)
Water resistance Printability in offset printing

7/9 7/9 9/11 9/11 56 56 60 60 0.95 0.98 1.01 1.02 84.5 84.2 83.8 83.4 83.1 85.6 82.6 85.0 50.6 48.7 35.3 33.1 A. A. D. D. A.
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Be i si) i e 1 11 to 14

The base paper of Examples 11 to 14 is the same as that of Example 3- 4 different coating compositions are prepared which contain the same bolystyrene emulsion as in Example 1, and applies it to the base paper. A coated one is obtained Synthetic paper. The mixing ratios of the coating agents are shown in Table IV (weight of pesticides).

Comparative example 8

The base paper is the same as in Example 3. A coating agent is applied which does not contain polystyrene emulsion on the base paper. A coated synthetic paper is obtained in this way. The mixing ratio of the coating agent can be seen from Table IV (Peststoffgewich ^).

The combined properties of those according to Examples 11 to 14 as well as The coated synthetic papers obtained in Comparative Example 8 are shown in Table IV.

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Table IV

Comparative example

45 34 21

7 14

Kaolin quality no.1 Kaolin quality no.2 aluminum hydroxide
Polystyrene
oxidized starch
Styrene / butadiene latex

Properties of the
coated paper

Application weight (g / m ² ) 9/11 (felt side / wire side)

Paper weight (g / m) density (g / cm)
Whiteness (^)
opacity (? £) gloss (? £)
Water resistance

Printability at
Offset printing D

-Example
12 13

42.7
32.3
20.0

7th
15th

36.0
27.2
16.8
20th
7th
16

22.5
17.0
10.5
50
7th
19th

0 0 0

100

8/10 7.5 / 9.5 5/6 3.5 / 4.3

60 58 57 51 47.8 1.05 1.03 1.01 0.92 0.85 82.3 82.9 83.3 84.1 84.6 86.1 86.5 86.8 87.0 87.2 38.4 45.5 51.1 52.6 52.5 D. B. A. A. A.

Table IV shows that those obtained in Examples 11-14 In comparison to that of Comparative Example 8, coated synthetic papers have a superior offset printability and a have good ink absorption. It is also stated that that in Example 11 to 14 different physical and chemical properties are significantly improved and that these improvements depend on the amount of polystyrene used. the improved offset printability is achieved with a relatively small amount of the polystyrene-containing coating agent. Thief means that according to the invention the weight of the coated synthetic paper can be decreased without deteriorating the other properties.

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Example 15 Ms 29

The base paper corresponds to that of example 12. They are different Coating agents which contain different organic polymers according to Table V are applied to the carbon paper sheet. Coated papers are obtained in this way. The other conditions are the same as in Example 12. The offset printability each of the coated papers obtained in these examples can also be seen in Table V. According to papers coated in these examples with improved offset printability.

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With- Verfor- Through- printing play mungstem- cutability

temperature grain size for offset (ji) printing

15 polyvinyl chloride 64 0.4 A

16 polyethylene (low density) 45 *) 0.9 B

17 polypropylene 99 *) 0.8 B.

18 ethylene / propylene block copolymer

(15: 85) 85 *) 0.8 B.

19 poly-4-methyl-i-pentene 180 0.7 A

20 polymethyl acrylate 97 0.4 A

21 polyvinyl acetate 38 0.5 B

22 ethylene / vinyl acetate copolymer

(92 t 8) 40 *) 0.5 B.

23 ethylene / propylene random

polymer (3: 97) 65 *) 0.5 B

24 styrene / aeryl nitrile copolymer

(76 ϊ 24) 92 0.3 A

25 styrene / maleic anhydride copoly-

meres (1: 1) (molar ratio) 140 0.3 A

26 ethylene / maleic anhydride copo-

lymeres (1 ϊ 1) (molar ratio) 170 0.5 B

27 sodium salt of ethylene / acrylic

acid copolymer (90:10) 88 0.4 A

28 styrene / acrylonitrile / itaconic acid—

-Copolymer (92: 6: 2) 85 0.5 A

29 styrene / aeryl nitrile / ß-hydroxyethyl acrylate copolymer

(89: 6: 3: 2) 80 0.5 A.

Remarks;

1) Table Y shows the proportions in parts by weight (with the exception of Examples 25 and 26);

2) The deformation temperatures marked with a *) are for a pressure of 4.6 kg / cm, which is not marked for a pressure of 18.5 kg / cm is specified (in each case according to ASTM test standard D 648).

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Example 30 «Comparative Example 9

In Example 30, the coated papers are made by that the first coating layer (lower coating layer) and the second coating layer (upper coating layer), each of which has different components according to the table VI contains, on the same base paper as in Example 3 applies.

In Comparative Example 9, the second coating layer does not contain any Polystyrene emulsion. The proportion of each component of the coating agent is given in terms of weight of the solid substance. The properties of the coated paper obtained are also shown in Table VI.

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lie VI 2429029 T a b e - Example 30 Comparison example 9 first coating layer 75 # 2 quality kaolin 25th 75 Calcium carbonate 0.3 25th Sodium hexame thapho sphat . ¹ 5 0.3 oxidized starch 4th 15th Styrene / butadiene latex 4th second coating layer 32.4 No. 1 quality kaolin 24.5 . 45 No. 2 quality kaolin 15.1 34 Aluminum hydroxide 28 21 Polystyrene 7th 0 oxidized starch 16 7th Styrene / butadiene lat ex 14th

-M

Application weight (g / m) first coating layer (felt side / sieve side) second coating layer (mushroom side / sieve side) Paper weight (g / m) Density C g / eur) Whiteness {<$) Opacity, gloss (#)

Water resistance Printability in offset printing

6/8

6/8

3/5 3/5 62 62 1.03 1.08 81.8 81.1 86.8 86.0 58.3 42.5 A. D. A. C.

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Claims (18)

Kanzaki-23 J * June 18, 197 ¹ I. Pat ent a n proverbs · The coated synthetic paper suitable for offset printing from a base paper sheet of fibrous material of which at least 5 wt -. $> From polyolefin-Papi he material are formed, and a formed on at least one surface of the base paper sheet coating layer, which consists essentially of Adhesive component and a pigment component is built up, at least part of the pigment component being an organic polymer pigment in the form of fine-grained particles. 2. Paper according to claim 1, characterized in that 5 to 95% by weight of the fiber material are formed from polyolefin pulp. 3. Paper according to claim 1, characterized in that the fiber material from a mixture of 5 to 95% by weight of a polyolefin paper stock and 95 to 5% by weight of a natural pulp is formed. 4. Paper according to claim 1, characterized in that at least 5 wt .- ^ (dry substance) of the pigment component is an organic Represent polymer pigment in the form of fine-grained particles. 5. Paper according to claim 1, characterized in that at least 10 wt. -I * (dry substance) of the pigment component represent an organic polymer pigment in the form of fine-grained particles. 6. Paper according to claim 4, characterized in that the pigment component from a mixture of an organic polymer pigment in the form of fine-grained particles and an inorganic one Pigments. 7. Paper according to claim 1, characterized in that the proportion the adhesive component is 5 to 100 parts by weight per 100 parts by weight (dry matter) of the pigment component. - 27 409882/0934 Kanzaki-23 % Z 8. Paper according to claim. 1, characterized in that the proportion of the adhesive component 8 to 35 parts by weight per 100 Parts by weight (dry matter) of the pigment component is 9. Paper according to claim 1, characterized in that the organic polymer pigment consists of fine-grained particles of an organic polymer with a deformation ^{temperature of more than 30 0} C according to ASTM test standard D 648. 10. Coated synthetic paper suitable for offset printing, characterized in that the organic polymer pigment consists of fine-grained particles of an organic polymer with a deformation ^{temperature of more than 50 0} C according to ASTM test standard D 648. 11 · Paper according to claim 1, characterized in that the organic Polymer pigment made from fine-grained particles with an average grain size of 0.1 to 1 μm. consists. 12. Paper according to claim 1, characterized in that the organic Polymer pigment consists of fine-grained particles of a vinyl polymer. 13 · Paper according to claim 1, characterized in that the organic Polymer pigment made from fine-grained particles of polystyrene, polymethyl acrylate or their copolymers with a any other vinyl monomer. 14. Paper according to claim 1, characterized in that 'that the weight of the Überzi
punch) is the weight of the coating layer is at least 0.5 g / m 15. Paper according to claim 1, characterized in that. that weight of the coating layer is 3 to 30 g / m 2 (dry substance). 16. Paper according to claim 1, characterized in that the poly - 28 - 409882/0934 olefin paper stock is made up of pibrils and a special 2 has a fish surface of at least 0.7 m / g. 17 · Paper according to claim 1, characterized in that the polyolefin paper stock is composed of a polyolefin polymer and a hydrophilic polymer. 18. A method for producing a coated synthetic paper suitable for offset printing, characterized in that a base paper sheet is produced from fiber material, of which at least 5% by weight are formed from polyolefin paper stock, and applying a coating to at least one of the surfaces of the base paper sheet with the aid of a coating agent, which consists essentially of an adhesive component and a pigment component, at least one Part of the pigment component is an organic polymer pigment in the form of fine-grained particles. - 29 409882/0934